1. Bruno, A. D.: Asymptotic Solving Essentially Nonlinear Problems. Mathematics and Statistics, 4:1, 27-39 (2016). DOI: 10.13189/ms.2016.040104.
2. Bruno, A. D.: Power Geometry in Algebraic and Differential Equations. Moscow, Fizmatlit, 1998. 288 p. (Russian) = Power Geometry in Algebraic and Differential Equations. Elsevier Science (North-Holland), Amsterdam, 2000. 385 p (English).
3. Bruno, A. D.: Asymptotics and expansions of solutions to an ordinary differential equation. Uspekhi Matem. Nauk 59:3, 31–80 (2004) (Russian) = Russian Mathem. Surveys 59:3, 429–480 (2004) (English)
4. Tikhomirov, V. M.: Fréchet differential. (https://www.encyclopediaofmath.org/index.php/Fréchet_differential). Encyclopedia of Mathematics, Springer, (2001).
5. Bruno, A. D., Goryuchkina, I. V.: Asymptotic expansions of solutions of the sixth Painlevé equation. Trudy Mosk. Mat. Obs., 71, 6–118 (2010) (Russian) = Transactions of Moscow Math. Soc., 71, 1–104 (2010) (English).